Method of forming split ring gears



Sept. 1945- R. .1. EISEMAN ETAL 2,385,617

METHOD OF FORMING A SPLIT RING GEAR Filed Sept. 4, 1942 2 Sheets-Sheet /e INVENTORS. E055? T J. [/SEMQIV p 05527 E. WE/V/Vff.

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.R. J. EISEMAN ETAL METHOD OFFORMING A SPLIT RING GEAR Sept. 25, .1945.

Filed se 4', 1942 2 Shets-Sheet 2 W Fr INVENTORS. 05557 1/. f/JEMfl/V. FOBEETE. WENNEE.

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Patented Sept. 25, 1945 METHOD OF FORMING SPLIT RING GEARS Robert J. Elseman and Robert E. Wenner, Cleveland, Ohio, assignors to Jack & Heintz, Inc., Bedford, Ohio, a corporation of Ohio I Application September 4, 1942, Serial No. 457,246

1 Claim.

This invention relates in general to gears and method for forming gears and has as its principal object to provide an improved labor saving process of forming the body portion and the teeth of a split ring gear.

With the foregoing, object in view, the invention will become apparent upon further reading of the following specification 'and appended claim, certain embodiments thereof being illustrated in the accompanying drawings, in which:

Figure 1 is a viewin vertical section taken through the drill press, showing the ring in completely formed position thereon;

Figure 2 is a view in elevation partly broken away showing the flat blank strip of metallic material with the initially formed teeth;

Figure 3 is a view in section taken along the line 3-3 of Figure 2; a

Figure 4 is a top'plan view of the fiat strip partly broken away shown in Figure 2; 1'

Figure 5 is a top plan view partly broken away showing the fiat strip of Figure 2 formed in a curve prior to the punch press operation;

Figure 6 is a view in section taken along line 6-6 f Figure 5;

Figure 7 is a top plan view partly broken away of the finished ring gear withrthe teeth properly angled after the punch press operation;

Figure 8 is a view in section taken along line 8-8 of Figure '7; and

Figure 9 is a view in section taken through a ring gear formed by a modified punch press operation to comprise a bevel gear and showing in dotted lines a pinion gear meshing therewith.

Referring more particularly to the drawings and as shown in Figures 2 and 3 the first operation is the obtaining of a flat strip of material of some suitable aluminum alloy and'the forming of the body portion I thereof by any suitable punch press operation of a series of teeth 2 in one edge of the flat strip which in fact are roughly approximate the teeth of the finished article. This well known conventional operation is a simple one and may be carriedon in multiple quantities.

The next operation is to take the flat strip of material formed with teeth shown in Figure 2 and by any suitable well known means curve the same into ring form as shown in Figure 5 without any alteration of the shape or angle of the teeth.

The final operation which is brought about by means yet to be described is the one single punch press operation to bring about the formation of a bead on the ring and the correction of angle v dotted lines 4 and 5 show the boundary lines of of the teeth so that they will properly mesh with a pinion gear.

The conventional practice in the formation of split .ring gears of this sort would constitute the formation of the teeth as shown in Figure 2.

the'teeth to be parallel as a natural consequence of the mere bending into ring formation of the ary lines of each tooth such as that shown by lines 6 and I converge at an imaginary center point 8 so as to constitute a proper angle for meshing with a pinion and also to constitute a very definite modification of tooth formation from that shown in Figure 5.

If desired the tooth formation of Figure 5 may take the form of a bevel gear as illustrated in Figure 9 in which the bevel tooth 9 is shown in mesh with the teeth l0 and the bevel pinion gear H, which of course would necessitate the corresponding formation of the master gear.

As one preferred means for accomplishing the previously described result there is illustrated in Figure 1 a punch press including a base l2 and a die comprising two complementary parts [3 and I have their inner portions offset and the inner portion l6 of the die 13 is formed with a specially accurately machined master set of angularly disposed teeth. The purpose of the oil?- set relationship of the inner portion of die M with respect to die I3 is to provide for the formation of the bead 'l! of the finished ring gear product. The line l8 indicates the two terminals of the ring gear formed of the coil strip. In

the particular use for which present ring gears are designed it is not necessary that it be a continuous piece or that the-.5 Wo ends be securely fastened to each other. -I\

As a further portion of the punch press the removable body portion consists of the bo dy l9 and cap 20 which is secured thereto by the bolt 2| 1 with an interposed. series of compression springs 22 to constitute the exterior limit of expansion of the material to be worked upon during the punch press operation. As an interior ureto that shown in Figures 7 or 9. re

' suit is brought about by reason of the fact rat limit there is provided a drill including a main\ body portion 23 and a cutout portion 24 which is secured to the head 25 by means of pins -26,

the head including a rod 21 provided with a cross pin 28 for attachment to a suitable'source of power.

As stated before the first operation in the present process is the stamping out of teeth in one edge of a simple flat piece of suitable material to take the form shown in Figures 2 and 3. The

next step is the simple bending of the strip of material without any thought of formation of a bead or of changing the angle and shape of the teeth so' as to take the form as shown in Figure 5 in which the boundary lines of the teeth are parallel and therefore unsuited for use as a ring gear for meshing with a pinion. The final operation is the forming of the stripshown in Figures 7 or 9 by means of a simple punch press as shown in Figure 1 by the mere placement of the ring toothed strip of Figur 5 in the punch press of Figure 1 and the one simple punch press'operation which results in the formation of the head I! and the change in shape and angularity of the teeth from that shown in Figpredetermined length, the bending of the the ofiset relationship of the interior shoulders of dies l3 and I4 is such as to bring about the displacement of the material of the strip so as to form the bead I! and also by reason of the fer-t that the teeth N5 of the die i3 have been equally machined to form a master die for the result ant formation of the teeth in the proper angular relationship shown in Figure 7 whether the teeth be that of an ordinary ring gear as shown in Figure 7 or a bevel gear as shown in Figure-.91

' From the foregoing it will be seen that there has been provided a new and novel labor saving method and means of converting a toothed strip of metallic material into a properly formed t t ring gear through the medium of a simple eingie punch press operation.

7 We claim:

Th method of forming a split ring of a fiat strip of material comprising th cutting of teeth in one edge of the flat strip into a circular form, and the suhseqi subjecting of the circular strip to an edge force of a punch pressing operation to mate alter the formation of the teeth by displacerr nt into one in which the boundary lines of the teeth when projected converge approximately at the center of the circular strip and simultaneously,

- by displacement of material, alter the form of the sides of the circular strip to assume a circular bead in the body portion of the strip.

ROBERT J. EISEMAN. ROBERT E. 'WENNER. 

